Alarm.



I IN E W /5 :B

W. SANDHAM.

ALARM.

APPLICATION FILED MAR. 2.0. 1913.

1,07 1 ,1 82, Patented Aug. 26, 1913.

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34 WlTNE SSE S.

I NTOR ATTORNEY.

COLUMBIA PLANGORAPH c0., WASHINGTON. D. c.

UNITED STATES PATENT OFFICE.

WALTER SANDI-IAM, 0F BAKERSFIELD, CALIFORNIA.

ALARM.

To all whom it may concern:

Be it known that I, WVALTER SANDHAM, a citizen of the United States of America, residing at 400 Kentucky street, city of Bakersfield, county of Kern, State of California, have invented a certain new and useful Alarm; and I do hereby declare the following to be a full, clear, and exact description of the invention, such as will enable others skilled in the art to which it appertains to make and use the same.

This invention relates to automatic alarms, and it may be said to consist in the provision of the novel and advantageous features and in the novel and improved construction, arrangement, and combination of parts as will be apparent from the description and claim which follow hereinafter.

- One object of the invention is to provide a novel and improved alarm which is adapted to be placed in an elevated position on door-knobs and other movable parts and which is actuated, in case it is placed on a door-knob as shown in this instance, when the door-knob is turned and thereby causes a drop of the alarm and a resultant pull of a cord or chain which draws the dog out of engagement with the strikin mechanism so that the latter is rendered efiective to sound an alarm.

Further objects of the invention are to provide a novel and improved alarm of the nature specified, which is simple in character, economical to manufacture and install, readily applied in service, effective in action, convenient and durable in use, and in which the parts may be quickly assembled.

Other objects and the advantages of the invention will be apparent to those skilled in the art from a consideration of the following description of the preferred form of construction of an alarm embodying the invention, taken in connection with the accompanying drawings which illustrate one application of the invention and in which drawings Figure 1 is a view of a fragment of a door and of the alarm operatively connected to the door-knob; Fig. 2 is a partly broken and sectional view taken on the line 2-2 of Fig. l--the alarm in its lowered position being indicated by dotted lines; Fig. 3 is a partly broken side elevation of the alarm with the retaining nut removed; Fig. 4 is a partly Specification of Letters Patent.

Application filed March 20, 1913.

Patented Aug.26, 1913.

Serial No. 755,771.

broken side elevation with the retaining nut and one of the bell plates and cheek plates removed; Fig. 5 is a sectional view taken on the line 5 of Fig. 3; Fig. 6 is a partly broken and sectional view of the alarm taken on the line 66 of Fig. 1, and Fig. 7 is a view-partly broken-similar to Fig. 4 but with parts shown in changed position.

The frame 8-on which is mounted the spring-operated striking mechanism 9 and also the spring-pressed dog 10 which is normally in engagement with the striking mechanism 9 to prevent operation thereofconsists of cheekplates l1 and 12, spacing sleeves 13 extending between the cheekplates 11 and 12, and bolts 14 passing through one of the cheek-plates and through the sleeves 13 and screwed into the other of the cheek-plates.

The striking mechanism 9 may consist of the following construction: The power shaft 15 has one end thereof bearing in the cheekplate 11 and passes through a suitable bearing in and extends beyond the cheek-plate 12. A helical spring 16 has one end thereof connected to the shaft 15 and has the other end thereof attached to one of the spacing sleeves 13. A ratchet wheel 17 is mounted fast on the shaft 15 alongside of a toothed wheel 18 which is loosely mounted on the shaft 15 and has pivotally mounted thereon a dog 19 which latter has the free end thereof pressed into engagement with the ratchet wheel 17 by the spring 20 which is mounted on the toothed wheel 18. A countershaft 21 has the ends thereof bearing in the cheekplates 11 and 12 and has thereon the lantern wheel 22 which is arranged in mesh with the toothed wheel 18 and has secured thereto the toothed wheel 23. Adjacent to the countershaft 21 is arranged the rocker shaft 24 which has the ends thereof bearing in the cheek-plates 11 and 12 and which is operatively connected with the toothed wheel 23 by means of the escapement 25. The striker 26 is connected to the rocker shaft 24 by an arm 27 and is adapted to be vibrated when the rocker shaft 24 is operated.

The cheek-plate 11 has thereon a stub shaft 28 on which is fitted a hollow dishshaped metallic part 29; a spacing washer 30 being interposed between the cheek-plate 11 and the part 29, and a nut 31 being screwed on the end portion of the stub shaft 28 to hold the part 29 in position. Another hollow dish-shaped metallic part 32 is fitted fast on the shaft 15 between the spacing washer 33 and the nut 34: on said shaft. By turning the part 32 the shaft 15 is turned to wind the spring 16. V

The dog 10 is pivotally mounted on a shaft 35 extending between the cheek-plates 11 and 12 and is normally pressed into engagement with the toothed wheel 18 by a spring 36 which latter may be looped around the shaft 15 and has one of its end portions bearing against one of the sleeves 13, and has the other of its end port-ions bearing against the dog 10. A cord or chain 37 has one end portion thereof suitably aflixed to a projecting portion 38 on the dog which projecting portion 38 extends upwardly through a .slot 39 in the part 29. The other end portion of the cord or chain 37 may be suitably afiixed on the shank 40 of the door-knob 41.

From the foregoing, it will be understood that in use the alarm may be disposed in elevated position by placing the cord or chain 37 over the top of the door-knob 41, so that when the door-knob 11 is turned the alarm will fall to a lower position and in consequence the pull on the cord or chain 37 will disengage the dog 10 from the toothed wheel 18 and the striker 26 will be vibrated and impinge the part 32 which being a bell plate sounds an alarm.

WVhile one form of construction embodying the invention has been illustrated and described there are various changes and modifications thereof that will readily occur to those skilled in the art, Wherefore the right is reserved to all such changes and modifications as do not depart from the Copies 01 this patent may be obtained for five cents each, by addressing the Commissioner of Patents,

spirit and scope of the invention as defined in the appended claim.

I claim:

The combination with a door knob, of an alarm consisting of a frame, a shaft rotatively mounted on said frame, a spring having one end thereof connected to said shaft and having the other end thereof connected to said frame, a bell plate mounted fast on said shaft, said bell plate adapted to be turned to turn said shaft to wind said spring, striker mechanism operatively connected with said shaft and adapted to impinge said bell plate to sound an alarm, said striker mechanism including a toothed wheel mounted on said shaft, a spring-pressed dog pivotally mounted on said frame and adapted to engage with said toothed wheel to prevent operation of said striker mechanism, and a chain having one end thereof connected with said dog and having the other end thereof aflixed to said door knob, said chain adapted to be placed over the top of the door knob to dispose the alarm in elevated position so that when the door knob is turned the alarm will fall to a lower position and in consequence the pull of the chain will disengage the dog from the toothed wheel to permit operation of the striker mechanism, substantially as set forth.

In testimony whereof, I have signed my name to this specification in the presence of two subscribing witnesses at Bakersfield, county of Kern, State of California, this 13th day of March A. D. 1913.

lVALTER SANDHAM. WVitnesses E. H. CLARE, C. H. FRANEY,

Washington, D. G. 

